GNU SAUCE

Blurb

SAUCE (Software Against Unsolicited Commercial Email) is an SMTP
server that sits between the Internet and your actual mail software.
It was originally written to help in the fight against spam, but it
also helps encourage good configuration and administration in general.

SAUCE has various tactics for reducing incoming spam:

Extremely aggressive checks on incoming email and its sources.
If any problems are discovered the mail is not accepted.

Spambait addresses: when mail is sent to a bait address its
sources are blacklisted.

Mail from previously-unknown sources is delayed to give them a
chance to try a bait address or get their account cancelled.

Pros:

SAUCE is very sucessful. It can cut spam by an order of magnitude.

Administrators using SAUCE have to deal with much less bounced mail.

SAUCE never bounces legitimate mail from correct, non-spamming sites.

Cons:

Most spam sources are misconfigured, but many other sites are too,
and SAUCE will bounce their mail. SAUCE is not for you if clueless
strangers often send you mail that's important to you.

SAUCE delays mail from new senders and sites (configurable, though).

SAUCE is something of a resource hog.

SAUCE is hard to install, especially if you're not using Debian.

SAUCE is controversial, because it deliberately rejects mail for
technical deficiencies which wouldn't make it undeliverable.

SAUCE is not a users' mailer. It must be installed on a mail hub by
the system administrator. It needs existing SMTP software, which must
have standard anti-spam features such as relay prevention, checking
recipients during the SMTP conversation, etc. Currently you must be
using Exim, though support for
other mailers could be added.

Feedback

If you are subscribed to sauce-discuss please send bug
reports there; otherwise mail them to
sauce-bugreports@chiark.greenend.org.uk.

Mailinglists

I have set up mailinglists sauce-announce and
sauce-discuss. The announcements list is moderated and
will contain only announcements of important bugs, new versions, &c.
The bug reports address mentioned above is also a mailing list; feel
free to subscribe to it.

There are
archives
and subscription web pages, or you can subscribe by sending mail
containing the word `subscribe' to
sauce-announce-REQUEST@chiark.greenend.org.uk or
sauce-discuss-REQUEST@chiark.greenend.org.uk.

SAUCE is also from the GNU Project
FTP servers and their mirrors, and as a package
for Debian (in the
project/experimental section).

Copyright and licensing

SAUCE is Copyright 1997-2001 Ian Jackson.

SAUCE is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or (at
your option) any later version.

This program and documentation is distributed in the hope that it will
be useful, but without any warranty; without even the implied
warranty of merchantability or fitness for a particular
purpose. See the
GNU
General Public License for more details.

You should have received a copy of the GNU General Public License
along with SAUCE, or one should be available above; if not,
write to the
Free Software Foundation,
59 Temple Place - Suite 330, Boston, MA 02111-1307, USA,
or email sauce-maint@chiark.greenend.org.uk.